Needle biopsies

Needle biopsies
can be performed with either a very fine needle or a cutting needle
large enough to remove a small nugget of tissue.

Fine-needle aspiration,
as noted above, uses a fine-gauge
needle and syringe, either to remove fluid from a cyst or clusters
of cells from a solid mass. Accurate fine-needle aspiration biopsy
of a solid mass takes great skill, gained through experience with
hundreds of cases.

Core needle biopsy
uses a somewhat larger needle with a
special cutting edge. The needle is inserted, under local
anesthesia, through a small incision in the skin, and a small core
of tissue is removed. This technique may not work well for lumps
that are very hard or very small. Core needle biopsy may cause some
bruising, but rarely leaves a scar, and the procedure is over in a
matter of minutes.

At some institutions with extensive experience, aspiration
biopsy is considered as reliable as surgical biopsy, trusted to
confirm the malignancy of a clinically suspicious mass or,
alternatively, to support a benign diagnosis for a breast lump that
appears noncancerous. Should the needle biopsy results be
uncertain, the diagnosis is pursued with a surgical biopsy. At some
institutions, doctors prefer to verify all aspiration biopsy
results with a surgical biopsy before proceeding with
treatment.

Localization biopsy
(also known as needle localization)
is a procedure that uses mammography to locate and biopsy breast
abnormalities that can be seen on a mammogram but cannot be felt
(nonpalpable abnormalities). Localization can be used in
conjunction with surgical biopsy, fine needle aspiration, or core
needle biopsy.

For a surgical biopsy, the radiologist relocates the abnormality
on a mammogram (or a sonogram) just prior to surgery. Using the
mammogram as a guide, the radiologist inserts a fine needle or wire
so the tip rests in the suspect area-typically, an area of
microcalcifications. (The breast may look bizarre with a needle
sticking out of it, but the procedure is remarkably pain free.) The
needle is anchored with a gauze bandage, and a second mammogram is
taken to confirm that the needle is on target.

The woman, along with her mammograms, goes to the operating
room, where the surgeon locates and cuts out the needle-targeted
area. The more precisely the needle is placed, the less tissue
needs to be removed.

Sometimes the surgeon will be able to feel the lump during
surgery. In other cases, especially where the mammogram showed only
microcalcifications, the mass can be neither seen nor felt. To make
sure the surgical specimen in fact contains the abnormality, it is
x-rayed on the spot. If this
specimen x-ray
fails to show
the mass or the calcifications, the surgeon is able to remove
additional tissue.